The Zeus can't deliver chip ram, as the Zeus plugs into the processor slot. There's no way to mess with the chip mem, which is at the other end of the bus. Zeus can do all kinds of trickery, even reroute chip men access for the CPU but it can't fool the other chips that can access chip ram via DMA.

Wouldn't it be possible if you disabled the onboard chipmem, like disconnecting their CS and having Zeus doing that? It's not exactly plug and play then, but would avoid needing any chipmem expansions.